Obstetric Events

Amniotic Fluid Embolism (Anaphylactoid Syndrome of Pregnancy)

Definition

Amniotic fluid embolism (AFE) is thought to be an abnormal maternal immune response to fetal antigens when the maternal-fetal immunological barrier is breached during labor, pregnancy termination, or shortly after delivery. It results in a triad of hypoxemia, hypotension, and coagulopathy.

Etiology

The etiology of cardiovascular collapse is not clear but may result from activation of a cascade of immune mediators that causes a massive systemic reaction

Management

Patients with AFE can rapidly deteriorate, are at high risk of maternal mortality, and have a high incidence of fetal distress. The key steps are early recognition, supportive management, prompt resuscitation, and delivery of the fetus.

Management

The key steps are early recognition, prompt resuscitation, and delivery of the fetus. Attempts to transfer patients undergoing CPR to an OR for immediate cesarean section increase maternal and neonatal risk. Perimortem cesarean section should be performed at the site of the arrest to relieve aortocaval compression, increase maternal CO and allow more effective chest compressions.

Prepare for stat cesarean section at the site of the arrest with the goal of delivery within 5 minutes

A cesarean section will be necessary if no return of spontaneous circulation after 4 minutes

Call for the crash cart

Apply defibrillation pads on chest

Do not delay defibrillation for shockable rhythms

Start CPR immediately (C-A-B: compressions, airway, breathing)

Chest compressions

Place hands slightly higher on sternum

Compressions should be at least 100 per minute and at least 2 inches deep

Rotate compressors every 2 minutes

Allow for complete recoil of the chest with each compression

Interruptions in compressions should be less than 10 seconds

Adequate compressions should generate an ET CO 2 of at least 10 mm Hg and a diastolic pressure of greater than 20 mm Hg (if an arterial line is in place). You MUST improve CPR quality if above conditions are not met.

Airway/ventilation

Until the patient is intubated, establish bag mask ventilation with 100% O 2 at a compression to ventilation ratio of 30:2 and prepare for endotracheal intubation

Place ETT and then ventilate at a rate of 10 per minute with continuous compressions

Assign tasks to skilled responders

Ensure adequate IV access

If difficult IV access, place IO line

Place an arterial line

Call for TEE or TTE machine

Turn off ALL anesthetics if in use (including epidural infusions)

Follow BLS and ACLS guidelines (see Event 2, Cardiac Arrest ) but with modifications for the parturient (see the following)